The ATT, approved by the U.N. General Assembly on April 2, 2013, is the first international pact to regulate trade in conventional arms, like small arms, battle tanks, combat aircraft and warships.

It will come into force when ratified by 50 countries while 11 states have already ratified the treaty.

The treaty would ban importing, exporting or brokering arms deals if there are risks that the weapons could be used for terrorism or genocide, or the trade would violate a U.N. Security Council resolution.

Japan seeks to approve the bill by the end of the current Diet session in June.

But some experts question whether this position is consistent with Prime Minister Shinzo Abe's drive to review the current restrictive policy on Japan's arms exports and set new guidelines.